5 year old started wetting again,frustrating!

DS (5) has been dry at nights for well over a year bar the odd accident maybe once every month or 2, but has recently started setting again almost every night.

It's a problem as pull ups won't contain it all so he's waking to a wet bed around 530 most mornings and won't sleep again after which is adfecting his mood/behaviour.

It has pretty much coincided with new baby being born-could it be some sort of regression or attention seeking?

He has no drinks for a good hour before bed, and always has a "last week" before he's put down, is there anything else I can do? Baby is messing with my sleep enough on his own, I could really do with the 5 year old sleeping longer!